1. Filed of the Invention
The present invention relates to welding situation and state recording process and system, which are capable of recording a welding situation and a welding state for a weld zone in a regeneratable manner.
2. Description of the Related Art
In general, metallurgically joining processes for joining two members to each other include a welding process. Such a welding process is used to joining metals to each other, a metal and a ceramics to each other and polymer materials to each other in the manufacture of a variety of articles such as a ship, a vehicle, a bridge, a common machine structure, electric article and the like. Such conventionally known welding processes include, for example, an arc welding process, a gas welding process, a thermit welding process, an electroslag welding process, an electron beam welding process, a lower-temperature welding process, a ultrasonic welding process, a plasma jet welding process, a laser welding process, a resistance welding process, a friction welding process, a gas welding process, a braze welding process and the like. A variety of welding machines for carrying out these welding processes have been proposed.
For example, a large-scaled automatic line for effectively welding a plurality of different weld zones by operating a resistance welding machine referred to as a spot welding machine, is used for the manufacture of a recent vehicle such as an automobile. The resistance welding machine used in such an automated line is employed in a welding robot capable of performing a variety of welding motions. In such a resistance welding machine, it is necessary to monitor and record the welding state of the resistance welding machine on real time basis in order to stabilize the welding quality. The monitoring and recording of welding information on the welding state for the weld zone welded by the welding machine, e.g., a current, (welding current), a voltage, a weld time, a current wave form, a weld force profile and the like, are carried out by a welding state detecting device.
In the conventional welding state detecting device, the welding information such as a current, a voltage, a weld time, a current wave form and a weld force profile for the weld zone during welding by the welding machine are recorded in a recording medium such as a recording paper, and the information on the welding situation such as the state of a work which is being welded is recorded manually on a recording paper by an operator.
In the conventional welding state detecting device, however, a heat-sensitive paper is used in many cases as the recording paper used as a recording medium for manually recording the information on the welding situation during welding. In this case, the following problem is encountered: the heat-sensitive paper is difficult to record manually, i.e., to write manually, and the heat-sensitive paper itself is sensitive to a heat and a chemical substance and hence, may be discolored in some cases in a factory in which the welding machine is placed. Therefore, the use of the heat-sensitive paper is not very preferred. Further, there is a problem that because it is common that the welding robot carries out the welding of a plurality of, e.g., ten weld zones in a short time, the manual recording of the information on the welding situation on the recording paper by the operator may be not in time for this welding in some cases.
When a flexible disk is used as the recording medium, the information on the welding situation is recorded on an individual recording paper, and the manual recording is carried out smoothly. However, when the welding of a plurality of weld zones is carried out in a short time, the following disadvantage incapable of being solved is encountered: The manual recording of the information on the welding situation by the operator may be not in time for the welding in some cases. Further, when the flexible disk is used as the recording medium, the following problem is encountered: Both of the flexible disk for recording the welding information and a recording paper for recording the situation information are required, and much labor is required both to manage a larger space for keeping in custody the flexible disk having the welding information recorded thereon and a recording paper having the situation information recorded thereon and to manage the flexible disk and the recording paper. When the flexible disk having the welding information recorded thereon and a recording paper having the situation information recorded thereon are individually kept in custody, there is a problem that much labor is required to make a one-to-one correspondence between the recording of the welding situation (situation information) and the recording of the welding state (welding information), when the meaning provided by the welding information is to be analyzed.
To solve the above problems, it is conceived that in addition to the recording of the welding information on the recording medium such as the recording paper by the welding state detecting means, the information on the welding situation is recorded, for example, on a magnetic tape by use of a sound recording device by an operator and kept in custody. In this case, the information on the welding situation can be recorded tactfully on the recording medium such as a magnetic tape, but there is problem that a welding state detecting device capable of recording the welding information on the recording paper and a sound recording device for recording the information on the welding situation are required individually. Further, another problem is that because the welding information and the situation information cannot be recorded together on a magnetic tape for recording the information on the welding situation, the magnetic tape having the situation information recorded thereon and the recording paper having the welding information recorded thereon are kept in custody individually, and hence, a large space for keeping both of the magnetic tape and the recording paper and much labor for managing both of the magnetic tape and the recording paper are required. A yet further problem is that when the magnetic tape and the recording paper are kept in custody individually, much labor is required for making a one-to-one correspondence between the recording of the welding situation (situation information) and the recording of the welding state (welding information), when the meaning provided by the welding information is to be analyzed.